Candidatus Rickettsia colombianensi in ticks from reptiles in Córdoba, Colombia

Background and Aim

Wildlife animals are reservoirs of a large number of microorganisms pathogenic to humans, and ticks could be responsible for the transmission of these pathogens. Rickettsia spp. are the most prevalent pathogens found in ticks. This study was conducted to detect Rickettsia spp. in ticks collected from free-living and illegally trafficked reptiles from the Department of Córdoba, Colombia.

Materials and Methods

During the period from October 2011 to July 2014, ticks belonging to the family Ixodidae were collected, preserved in 96% ethanol, identified using taxonomic keys, and pooled (between 1 and 14 ticks) according to sex, stage, host, and collected place for subsequent DNA extraction. Rickettsia detection was performed using real-time polymerase chain reaction (RT-PCR), followed by conventional PCR to amplify a larger fragment of the gltA and 16S rRNA genes. The amplicons were sequenced using the Sanger method, and the nucleotide sequences were subjected to BLAST analysis to identify homologous sequences in GenBank, after which phylogenetic analysis was performed using the MEGA X software.

Results

In total, 21 specimens of nine species of reptiles were sampled, from which 805 Amblyomma dissimile ticks were collected, but only 180 ticks were selected to create 34 groups. The DNA of Rickettsia spp. was detected in 30/34 (88%) groups. The sequences of the gene gltA and 16S rRNA revealed a 100% identity with Candidatus Rickettsia colombianensi (GenBank: KF905456 and GenBank: KF691750).

Conclusion

A. dissimile was the only tick found in all the sampled reptiles. The presence of Candidatus Rickettsia colombianensi in reptile ticks could represent a public health problem due to the risk of transmission to humans and the introduction of microorganisms to other geographical areas.

Evolution of Family Medicine in Kenya (1990s to date): a case study

Background: Successful Family Medicine practices and academic programmes are found in western countries, Australia, Singapore, Cuba and among other non-western countries. Documenting the enablers and challenges of different contexts would, it is hoped, inform current and future process of developing academic and practice programmes in Family Medicine in countries where the discipline is starting. Methods: A qualitative study was undertaken that conducted a focused literature review and in-depth interviews of key informants on the early development of the Family Medicine in Kenya. All interviews were audio recorded. Pattern matching, explanation building, time-series analysis and logic models were used in analysis. Results: Representatives of Kenyan and foreign organisations worked well as a team to write and implement the first curriculum of Family Medicine. The challenges include lack of teachers; starting a graduate programme in medical schools that did not have one and starting these health services delivery departments in a system that did not have any. Conclusions: The main enablers of the evolution of Family Medicine in Kenya include committed partnerships and teamwork among Kenyan and non-Kenyan stakeholders. The challenges include the lack of Kenyan teachers of the programme and the introduction of a new discipline. (Full text of the research articles are available online at www.medpharm.tandfonline.com/ojfp) S Afr Fam Pract 2017; DOI: /10.1080/20786190.2016.12481420

The proline-rich homeodomain (PRH/HEX) protein is down-regulated in liver during infection with lymphocytic choriomeningitis virus

The proline-rich homeodomain protein, PRH/HEX, participates in the early development of the brain, thyroid, and liver and in the later regenerative processes of damaged liver, vascular endothelial, and hematopoietic cells. A virulent strain of lymphocytic choriomeningitis virus (LCMV-WE) that destroys hematopoietic, vascular, and liver functions also alters the transcription and subcellular localization of PRH. A related virus (LCMV-ARM) that does not cause disease in primates can infect cells without affecting PRH. Biochemical experiments demonstrated the occurrence of binding between the viral RING protein (Z) and PRH, and genetic experiments mapped the PRH-suppressing phenotype to the large (L) segment of the viral genome, which encodes the Z and polymerase genes. The Z protein is clearly involved with PRH, but other viral determinants are needed to relocate PRH and to promote disease. By down-regulating PRH, the arenavirus is able to eliminate the antiproliferative effects of PRH and to promote liver cell division. The interaction of an arenavirus with a homeodomain protein suggests a mechanism for viral teratogenic effects and for the tissue-specific manifestations of arenavirus disease.

Role of the promyelocytic leukemia protein PML in the interferon sensitivity of lymphocytic choriomeningitis virus

Lymphocytic choriomeningitis virus (LCMV) induces type I interferon (alpha and beta interferon [IFN-alpha and IFN-beta]) upon infection and yet is sensitive to the addition of type II interferon (gamma interferon [IFN-gamma]) to the culture media. This sensitivity is biologically important because it correlates inversely with the ability of certain LCMV strains to persist in mice (D. Moskophidis, M. Battegay, M. A. Bruendler, E. Laine, I. Gresser, and R. M. Zinkernagel, J. Virol. 68:1951-1955, 1994). The cellular oncoprotein PML is induced by both IFN-alpha/beta and IFN-gamma, and PML binds the LCMV Z protein and becomes redistributed within cells from nucleus to cytoplasm upon LCMV infection. In the present study, increased PML expression results in diminished LCMV replication, implicating PML in the IFN sensitivity of LCMV. Virus production in PML -/- murine embryonic fibroblasts (MEF) exceeds virus production in PML +/+ MEF, and this difference is exacerbated by IFN treatment that upregulates PML expression. IFN-gamma also diminishes LCMV production in PML -/- cells; therefore, viral IFN sensitivity is not entirely due to PML. Both viral mRNA production and viral protein production decrease as PML expression increases. Here we propose that PML reduces LCMV transcription through its interaction with the Z protein.

Mucosal immunization with Salmonella typhimurium expressing Lassa virus nucleocapsid protein cross-protects mice from lethal challenge with lymphocytic choriomeningitis virus

OBJECTIVES

Lassa fever virus (LAS) is transmitted to man by rodent carriers and is fatal in a third of untreated cases. Our goal is to provide immune protection from Lassa fever by mucosal vaccination.

STUDY DESIGN/METHODS

Mice were vaccinated intragastrically with control vectors or with vectors (vaccinia or Salmonella) expressing LAS nucleocapsid protein (NP). Mice were challenged intracranially with a lethal dose of the related arenavirus, lymphocytic choriomeningitis virus (LCMV), as a measure of the vaccine's ability to elicit cross-protection.

RESULTS

Salmonella and vaccinia vectors expressing LAS NP each protected a third of the mice from lethal challenge with LCMV. All mice vaccinated with a vector expressing LCMV NP were protected as expected.

CONCLUSIONS

The LAS recombinant Salmonella vector is comparable to the LAS recombinant vaccinia vector in its ability to cross-protect mice from lethal challenge. Nucleocapsid protein is an inadequate immunogen on its own, but provides sufficient cross-protection to make it a useful component of a broadly reactive arenavirus vaccine.

Malignant myoepithelioma of the salivary glands: clinicopathological and immunohistochemical features

Malignant myoepitheliomas (myoepithelial carcinomas) are uncommon, and we know of only 29 reported cases. We present a new case together with its clinical, histological, and immunohistochemical features. The tumour was located in the inferior vestibular sulcus of a 64-year-old woman. She was treated by wide local resection. Malignant myoepitheliomas are distinguished from benign myoepithelial neoplasms by their infiltrating and destructive growth. The tumour cells may be spindle-shaped or more rounded (plasmacytoid cells) and contain cellular pleomorphism and mitotic activity. The clinical and biological behaviour of this tumour is not yet known and there is little information about treatment and prognosis.

Eosinophilic ulcer of the oral mucosa: report of a recurrent case on the tongue

Eosinophilic ulcer of the oral mucosa (EUOM) is an uncommon lesion that usually affects the tongue. The lesion is benign and self-limiting, develops rapidly and usually disappears after several weeks without treatment. Microscopically, it contains a diffuse polymorphous cell infiltrate composed mainly of eosinophils. The cause of EUOM is unknown, but the condition has been attributed to trauma. We now describe a case of EUOM on the lateral surface of the tongue with recurrence on its dorsal surface 3 years later. The occurrence of multiple lesions, whether at the same time or subsequently as reported here, makes a purely traumatic origin rather unlikely and suggests that there may be a predisposition of some patients to develop EUOM. Eosinophilic ulcer of the oral mucosa (EUOM) is an uncommon lesion that is very rarely reported in the dermatological literature. It usually affects the tongue and presents clinically as an ulcer with elevated and indurated borders. Recognition is important because it often mimicks tongue cancer; however, the lesion is benign and self-limiting, develops rapidly and usually disappears after several weeks without treatment. Usually the ulcer occurs in a single episode, but the possibility of recurrence at other sites has been poorly emphasized.

[Epidemiological and etiological aspects of upper digestive hemorrhage. Multicenter study in nine Chilean hospitals (1980-1990)]

An epidemiological survey about the incidence of upper gastrointestinal bleeding during three periods (1980, 1985 and 1990), was performed in 9 Chilean hospitals. Its annual incidence decreased in 1990, when compared to 1980. Likewise the etiologies changed, with an increase in the incidence of duodenal ulcers and a decrease in the incidence of erosive gastritis and bleeding of unknown origin in 1990. A seasonal variation with higher bleeding rates in autumn was also recorded.

[Presence of Helicobacter pylori in the duodenum, antrum, and fundus in control subjects and patients with duodenal ulcer, gastric ulcer, gastritis, or erosive duodenitis. Histological analysis of 357 subjects]

The prevalence of Helicobacter pylori infection was studied in 152 subjects with a normal upper gastrointestinal endoscopy, 125 with duodenal ulcer, 25 with gastric ulcer, 46 with erosive gastritis and 9 with erosive duodenitis. Two biopsies from duodenum, antrum and fundus were obtained from each subject during endoscopy for histological diagnosis and Helicobacter pylori search. None of the patients with normal endoscopy and 2% of patients with duodenal ulcers had Helicobacter pylori in duodenal biopsies. These last patients had a significantly higher frequency of Helicobacter pylori in the antrum (71%) than the rest of the studied groups. Five percent of subjects with normal endoscopy and 5% of those with duodenal ulcers had Helicobacter pylori in the antrum. An active gastritis was demonstrated in almost all patients with Helicobacter infection. Intestinal metaplasia occurred almost exclusively in the absence of Helicobacter pylori infection.